Ribbon yarn

ABSTRACT

Described is a ribbon yarn made of multifilament yarns based on polyamide and/or polyester, wherein not more than 5 filaments overlie one another within the ribbon yarn, wherein the ribbon yarn is fixed by the formation of a matrix comprising one or more fixing agents, wherein the one or more fixing agents are selected from a group consisting of copolyamides, copolyesters, silicones, and mixtures or blends thereof.

This is a Division of application Ser. No. 14/377,636 filed Aug. 8,2014, which in turn is a National Stage Application of PCT ApplicationNo. PCT/EP2013/052596 filed Feb. 8, 2013, which claims the benefit ofEuropean Patent Application No. 12154856.4 filed Feb. 10, 2012. Thedisclosure of the prior applications is hereby incorporated by referenceherein in its entirety.

BACKGROUND

The present invention relates to a method for producing a ribbon yarnand to the use of such a yarn, e.g. for producing airbag fabrics or tirereinforcements.

Ribbon yarns for the production of airbags are known for example fromEP-A-2 374 923. In this document, a plurality of yarns made ofindividual fibers are treated with an “activatable” additive or acoating and subsequently subjected to an activation step so that theyarns assume a flat configuration.

Airbags are typically constructed as woven fabrics and are initiallyfolded and/or rolled into a narrow package and inserted into an airbagmodule behind a cover.

The folded airbag is connected to a gas generator which is designed suchthat a large volume of gas is introduced directly following receipt of aso-called impact signal. In view of the very short time frame withinwhich an airbag is inflated in order to provide sufficient protectionfor a vehicle occupant in the case of a crash, substantial flow ratesare achieved and the gas is also, depending on the type of generatorused, very hot. For these reasons, it is common to provide the fabric ofthe airbag with a surface coating in order to achieve at least a shortterm heat resistance and to impede the permeability for hot particles.

Commonly, woven fabrics made of polyamide material are used for thispurpose, and the fabric is provided with a silicone coating in order toachieve a good seal tightness with respect to gases and particles. Atthe same time, this design enables a relatively good aging resistance ofthe airbag.

The disadvantage in this design is the considerable use of material forthe production of a relatively sealed fabric as well as for the coating.Due to the increasing prices for the synthetic polymers, generally basedon petroleum, for the production of the filaments, to the steadilyincreasing use of airbags in automobiles of all types, and to theextreme cost pressure within the automotive industry, possibilities mustbe sought for producing an airbag for which the material expense is aslimited as possible—without detriment to performance. Added to this isthe demand by the automotive industry for reductions in weight and spacerequirements for all parts used, thus also for the airbag.

JP 03 276845 (Bando Chem Ind Ltd.) proposes a method for producing aribbon yarn which contains the steps: provision of a yarn made ofmultifilaments, spreading the yarn, fixing the yarn by forming a matrixconsisting of an elastomer, and winding the yarn, wherein the spreadingis carried out such that not more than five filaments overlie oneanother.

In JP 04 015143 from the same applicant, a ribbon yarn is provided withan elastomer based on silicone rubber or resorcinol formaldehyde latex(RFL) in a so-called dipping facility.

Finally, US 2004/0043213 describes the spreading of carbon fibers inorder to obtain as large a surface as possible for coating with RFL, inorder to thereby guarantee that filaments located in the inside of thefilament bundle are also coated with the reagent.

BRIEF SUMMARY

The methods and the ribbon yarns of the prior art obtained from saidmethods still have, however, the disadvantage that the adhesion of thefilaments to the “activatable” additives or coatings in part leaves alot to be desired, in particular when it comes to the use of filamentsmade of polymers that do not have a good adhesion per se, such aspolyester.

By means of the present invention, this problem is solved by a methodfor producing a ribbon yarn comprising the following steps:

a) provision of a yarn made of multifilaments based on polyamide and/orpolyester,b) spreading the yarn such that not more than five filaments overlie oneanother,c) fixing the yarn by forming a matrix consisting of one or more(suitable) fixing agents,d) winding the fixed yarn, characterized in that the fixing agent oragents are selected from a group consisting of copolyamides,copolyesters, and silicones, and also mixtures or blends thereof.

For the method according to the invention, it is even more advantageousif the yarn made of multifilaments is spread so wide that not more thanthree filaments (individual filaments, thus endless fibers) overlie oneanother. In contrast, in EP-A-2 374 923 yarns are provided and saidyarns are then treated with an activatable additive or coating, and theribbon yarn structure is subsequently set by compression. Due to thespreading in the method according to the invention, however, asubstantially better degree of distribution of the fixing agent isachieved, by which means a significantly better adhesion occurs, even ifno subsequent compression treatment is carried out.

Preferably a thermoplastic copolyamide, especially preferably acopolyamide with a melting point between 120 and 150° C., is used as thefixing agent—in the following also designated as a binder—for formingthe matrix. As will be described in more detail below, the introductionpreferably takes place in aqueous and/or ethanol suspension or solution.

Alternatively, a reactive silicone, preferably in the form ofpolysiloxanes, can be used as a thermosetting fixing agent.

Especially well-suited for this purpose are polysiloxanes that contain(unsaturated) vinyl groups in the primary chain or in the side chains.Alternatively, copolyesters can also be used as binders.

It has been shown to be favorable for a series of applications—inparticular if silicones are used for the fixing agents—if a yarn made ofmultifilaments is used from which the finishing agents and sizing agentshave been largely removed beforehand.

The removal of the finishing or sizing agents is accomplished by washingprocesses known per se, but preferably by means of treatment usingso-called ramjet washers. A suitable ramjet washer is described forexample in EP-B-0711247. The positive effect resulting therefrom is thata washing process can be foregone after the subsequent weaving, becausethe fabric as such also shows outstanding resistance to burningaccording to EASC 3.12 or ISO 3795.

In addition, the washing process has the effect that the adhesion withrespect to the silicone coating (if this is still required) is improved.

Furthermore, it can be appropriate if the fixed yarn is calendered priorto winding, wherein a heatable roller pair is preferably used for thecalendering, but in particular a heatable roller trio is used.

The calendering has the effect, among others, that the ribbon yarnobtained becomes gas- or air-tight and can therefore mean that a coatingstep of the fabric, which usually takes place later, becomes obsoletedue to this “sealing effect”. The ribbon yarn becomes“displacement-proof” by means of the calendering.

For the method according to the invention, it is also preferred if thewinding of the yarns reinforced by means of the fixing agent isperformed without twist.

The yarns used contain preferably multifilaments made of polyamide,copolyamide, or polyester, and/or mixtures thereof. Among thepolyamides, the aliphatic polyamides polyamide 6, polyamide 6,6, andpolyamide 4,6 are eminently suitable. In principle, the use of aromaticpolyamides is also possible of course, for example polyparaphenyleneterephthalamide (PPTA).

Among the polyesters, polyethylene terephthalate (PET) and polylacticacid (polylactide, PLA) are especially suitable.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graphical representation of the results shown in Table 3.

FIG. 2 is an image of the device used to determine the flexural strengthof the fixed ribbon yarns.

FIG. 3 is a graphical representation of breaking tension at differenttemperatures.

DETAILED DESCRIPTION

The production of the ribbon yarns and the use thereof for e.g. theproduction of airbag fabrics or tire reinforcements, as well aspreferred embodiments, will now be explained in more detail.

A multifilament yarn is provided, for example, spun from polyamide 6,6with a linear density of 1880 dtex and 280 individual filaments. Themultifilament yarn is preferably provided in an unmingled state, i.e. nointermingling jets or other types of intermingling of the yarn are usedafter the spinning process.

The yarn can then be subjected to a washing process. The washing isrecommended, for example, if the fixing step should take place using areactive silicone, for example, a polysiloxane. The background is thatthe finishing or sizing agents negatively affect (increase) the burningbehavior during later applications, for example as an airbag.

If, for example, a copolyamide is used as a binder or fixing agent, thenthe later burning behavior is surprisingly not increased, even withregard to the fixing of unwashed yarns, that is, yarns that stillcontain finishing and sizing agents, in comparison to the washed yarns.It is conjectured that the finishing and sizing agent particles arequasi “encapsulated” due to the fixing with the copolyamide as a binder,and in this way can no longer increase the flammability. However, theadditional washing step has also proven to be advantageous when usingthe copolyamides.

As already stated above, it is especially advantageous if the (optional)washing is carried out with the aid of ramjet washers. A drying step canbe connected downstream of the washing process. The drying is in turnpreferably advised if, for example, a reactive silicone is used as abinder, since polysiloxanes react sensitively to the presence ofmoisture and phase separation with the water occurs. However, even whenusing copolyamides as a binder, the drying process can be advantageous,since the uniform application of the fixing agent consisting of aqueousand/or ethanol suspension or solution is occasionally difficult if themultifilament yarn is present in a moist or wet state.

Drying can take place in a manner known per se, for example by using ahot air stream, but drying is preferably in an oven. The drying iscarried out to a residual moisture content of less than 5 wt. %,preferably to the equilibrium moisture of the respective multifilamentyarn.

After the provision, and, if applicable, washing and drying, thespreading—or also filament separation—of the multifilament yarn takesplace. The (individual) filaments forming the multifilament yarn arethereby aligned parallel and side by side—e.g. mechanically by means ofpins, such that not more than 5, preferably not more than 3 individualfilaments overlie one another.

Thereafter, the application of the fixing agent on the multifilamentyarn spread in this way takes place. The application can take place as aforced application in a way known to a person skilled in the art anddepends substantially on the consistency and type of the binder, forexample, by means of a lick roller, by guiding through an immersionbath, by spraying on with a sprayer, or by a roller.

The applied amount depends on the type of multifilament yarn used and inparticular on the later area of use. Depending on the furtherprocessing, 0.1 to 30 wt. %, preferably 0.5 to 20 wt. %, more preferably1 to 10 wt. %, and most preferably 1 to 5 wt. %, relative to the weightof the multifilament yarn, can be used.

The fixing or curing takes place subsequently by means of reaction,residence time, and temperature, and preferably without application ofpressure.

If a polysiloxane is used, then it is preferably a cross-linkablesilicone from Wacker, which is sold under the name “DEHESIVE 920” orDEHESIVE 971. This product is a mixture containing a reactivepolysiloxane, which has vinyl groups within the chains or as sidechains, for example CH₂=CH—(Si(CH₃)₂-0)_(n)—CH=CH₂ where n is between 2and 200, preferably 10 and 100, and more preferably 20 and 50. Further,the mixture contains a short-chain silane (HX) as a cross-linking agentas well as a platinum catalyst (OL). The short-chain silane is able tobind to the vinyl groups of the polysiloxane and thus trigger thecross-linking. The viscosity of the reactive polysiloxane mixture isapproximately 500 mPa s. The special advantage of this reactivepolysiloxane lies in the fact that, with respect to a use of thethus-fixed ribbon yarn in the airbag, the subsequent coating withsilicone proceeds substantially more easily, since a pre-activation andthus an improved adhesion of the ribbon yarn has already occurred due tothis fixing. In the later airbag fabric, the film-forming characteristicis clearly more pronounced due to this, which becomes noticeable in astrongly increased adhesion compared to the conventional airbag coatingusing silicone rubber.

Surprisingly, the ribbon yarns coated with the reactive silicone have asignificantly improved anti-wicking behavior. This makes the ribbonyarns eminently suitable for applications in textile construction, wherethe wicking effect is highly undesirable. In addition, the ribbonproduced using silicone has a surprisingly increased cut resistanceduring weaving.

A further preferred fixing agent is “VINNAPAS 441”, an ethylene vinylacetate copolymer, likewise sold by Wacker.

Furthermore, copolyamides or copolyesters sold by EMS Chemie under thename “GRILTEX” are preferred as binders. These copolyamides andcopolyesters are offered either in aqueous suspension (e.g. Griltex 2A,40%) or as an ethanol/aqueous solution (e.g. Griltex D 1523A) and can beused in the method according to the invention either directly or dilutedto approximately 10 to 20%. Griltex® 2A Copolyamide Hotmelt Adhesive isparticularly preferred.

In contrast to the polysiloxane, the activation takes place here usingheat, since the copolyamide has a melting point range of approximately120 to 150° C. The use of the copolyamide has the major advantage that,for example, the airbag fabric contains only one type of material. Inaddition, it is possible, through a corresponding increase in theconcentration, to allow the film formation to take place solely by meansof the fixing agent, in that the copolyamide is only remelted afterproduction of the airbag fabric and the film formation is thustriggered.

It is particularly advantageous that the subsequent treatment withsilicone rubber for the airbag coating can be omitted. A closed surfaceis thus already formed on the fabric by the fixing agent.

The copolyamide is used particularly preferably as an aqueoussuspension, wherein the particle size of the copolyamide particlesshould be smaller than 1 μm on the average. In the particularlypreferred Griltex 2A, the particle size of 90 vol. % is a maximum of 0.9μm. This particularly preferred fixing agent is in effect an adhesive,which has, however, particularly good characteristics in the methodaccording to the invention, as can be seen below.

The particularly preferred copolyamide has a melting point range(determined via DSC) of 120-130° C., a glass transition temperature(T_(g)) (determined via DSC) of 17° C., a melt viscosity (mean accordingto ISO 1133 at 160° C./2.16 kg) of 600 Pa*s, a melt volume rate MVR(mean according to ISO 1133 at 160° C./2.16 kg) of 18 cm³/10 min, arelative viscosity (in 0.5% m-cresol) of 1.47, and a density (determinedaccording to ISO 1183) of 1.05 g/cm³. Suitable copolyamides and theproduction thereof are described for example in the embodiments of EP 1153 957 A2.

The applied amount of copolyamide on the yarns lies preferably in therange from 1 to 10 wt. % and particularly preferably 2-5 wt. %, relativeto the yarn amount. As already mentioned, the yarn amount variesdepending on the field of application of the ribbon yarn obtained. Thus,it can be appropriate to apply a relatively high amount of thecopolyamide if, e.g. it is desired to omit the previously necessarysiliconization of the later airbag fabric in order to already achievethe gas-tightness with the aid of the fixing agent and with a subsequentcalendering step.

A copolyester likewise sold by EMS Chemie represents a further preferredfixing agent in the method according to the invention, which copolyesteris used in particular for multifilament yarns made of polyethyleneterephthalate. A binder of this type proves to be eminently suitable,particularly for applications of the thus-fixed ribbon yarns in fabricsthat are later coated with PVC, as by this means the isocyanatesotherwise needed as adhesion promoters can be omitted.

After the coating and activation, the winding of the ribbon yarns thusobtained takes place. It is hereby recommended that the winding takeplace without twist in order that the “ribbon character” is not undoneagain. The winding takes place preferably with the aid of a new type ofwinder from Sahm, a parallel-bobbin winding machine, model Sahm 460 XE.The bobbin moves during the winding process on this winder, and not theribbon yarn, in order to prevent twists.

It is advantageous if the ribbon yarn is pre-tensioned by means of aroller pair, or preferably a trio of rollers, prior to winding, on theone hand to perform calendering but even more so to ensure a uniformtension, which should be as low as possible during the fixing step. Auniform tension of this type is also important for the uniform formationof the ribbons. For example, a tension in the range from approximately50 to 200 g has proven to be favorable for the polyamide multifilamentyarn 1880 dtex f 280.

With the aid of the winder and the uniform tension, the desired windingof the ribbon yarn without twist is already largely achieved.

The uniformity of the tension can still be additionally improved byusing tension-controlled unwinders. Examples of these are the GARunwinding creels from Karl Mayer and the Sahm Bitensor 910E unwindingunit from Sahm.

The ribbon yarns produced in this way are distinguished by excellenttenacity (important e.g. for airbags or for tire reinforcement) whilesimultaneously using significantly less yarn than in conventionalmethods. By this means, a substantial weight reduction arises, whichalso results, for example, in the improved packability of the airbag.

In the field of rubber reinforcement, rubber can be saved by the flatgeometry of the ribbon, such that, e.g. during use as steel-belt bindersin radial tires, the tire becomes lighter and has at the same time alower rolling resistance, since less rubber can be used between thesteel belt and the tread. The parallel orientation of the individualfilaments in the ribbon additionally effects a further increase of themodulus in comparison with the conventionally-used tire cord, such thatthe high-speed performance of the tire is further increased at the sametime.

An RFL dip (resorcinol formaldehyde latex dip) can therefore also beused as an additional fixing agent in the method according to theinvention. Resorcinol formaldehyde precondensates are known as anadhesion promoting component for rubberized fabrics. To produce the dip,the precondensate is thereby processed together with the latexdispersions and other ingredients to form so-called resorcinolformaldehyde latex (RFL) dips.

As carcass reinforcement in radial tires, e.g. for airplane tires, theseribbon yarns offer a higher modulus in comparison with cords made offilament yarns.

Likewise, the rubber adhesion or the adhesion to the polyvinyl chloride(PVC) is improved, since the effective adhesive surface is larger andalmost all filaments have an adhesive bridge to the rubber. In contrastthereto, in the case of round or twisted yarns, part of the filamentsare enclosed in the inside and have no contact/adhesion to thesurrounding matrix.

During the production of woven fabrics, the efficacy can be increased,since one can work with a substantially reduced weft insertion.

The weight savings by means of the high surface coverage of the ribbonyarns and the anti-wicking effect show very great advantages for textileconstruction. Fabrics of this type are also outstandingly suitable forthe production of sails.

In addition, the fact that the ribbon yarns have practically no “wickingbehavior” enables vastly improved recycling properties, since theaddition of often fluorine-containing additives to reduce the wickingeffect in conventional fabrics can be omitted.

The invention is likewise directed at ribbon yarns made of multifilamentyarns based on polyamide and/or polyester, wherein no more than 5filaments overlie one another within the ribbon yarn, wherein the ribbonyarn is fixed by the formation of a matrix consisting of one or more(suitable) fixing agents, wherein the fixing agent or agents areselected from a group consisting of copolyamides, copolyesters, andsilicones, as well as mixtures and blends thereof.

Preferably, not more than three filaments overlie one another within theribbon yarn according to the invention.

The ribbon yarn according to the invention has a width (tape width) ofat least 3.5 mm. In particular when using polyamide 6,6 filaments andthe copolyamide as a fixing agent, particularly preferably “GRILTEX 2A”,a good adhesion of the spread individual filaments is achieved in thecomposite. This is produced by the good thermoplastic moldability of thematrix. At the same time, however, this thermoplastic behavior of thematrix subsequently allows in the fabric for the individual ribbon yarnsin the warp and weft to be connected to each other to some degree byapplying heat and pressure to the finished fabric, such that the alreadymentioned sealing effect occurs here, which improves the gas-tightnessof the fabric and makes a subsequent coating with e.g. siliconesuperfluous, or significantly reduces the required amount of coating.

It is particularly advantageous that the resulting ribbon yarn remainsflexible in the temperature range of minus 30 to plus 110° C. typicalfor automobiles.

It was found to be particularly surprising that the flexibilitydecreased only minimally, even at very low temperatures caused bytreatment with liquid nitrogen. This qualifies the ribbon yarn accordingto the invention for additional applications that take place atextremely low temperatures.

The invention is further directed at airbag fabrics produced from theribbon yarns according to the invention, wherein said airbag fabrics areproduced without the conventionally necessary sizing during theproduction of the warp and without the conventional washing after theweaving, and, if applicable, can be used directly without theconventionally necessary subsequent coating to achieve gas-tightness.

The invention is to be explained in more detail on the basis of thefollowing examples:

Ribbon yarns made of polyamide filaments having a nominal linear densityof 1880 dtex f280 were produced. The textile data for the filaments usedis gathered in Table 1. The following meanings apply: LD=linear density(measured), EASF 45 N=elongation at a force of 45 N, EASF 90N=elongation at a force of 90 N, HAS 5 mN/tex=hot air shrinkage at apretension of 5 mN/tex (measured at 180° C. for 2 min).

TABLE 1 EASF EASF Breaking Elongation 1 2 HAS LD Breaking tenacity atbreak 45 N 90 N 5 mN/tex Work Trial [dtex] force[N] [cN/tex] [%] [%] [%][%] [N*cm] 140 HRT 1922 158.67 82.56 21.11 7.43 10.86 4.59 897.01 PAB2011-028 1934 156.49 80.91 19.77 7.08 10.55 5.17 818.01 PAB 2011-0311941 158.08 81.44 20.70 7.25 10.75 4.93 870.58 PAB 2011-044 1930 157.4581.58 20.45 7.06 10.50 4.95 862.42 PAB 2011-048 1920 157.29 81.92 20.447.30 10.87 5.04 848.97 PAB 2011-057 2011 158.95 79.04 23.18 8.06 12.303.17 970.07 PAB 2011-059 2007 153.95 76.71 22.01 8.84 13.13 2.83 824.99PAB 2011-060 1954 157.22 80.46 21.50 7.74 11.68 3.52 877.18

The ribbon yarns obtained from the filaments listed in Table 1 werefixed using different fixing agents. An overview of the fixing agentsand the fixing conditions is contained in Table 2.

TABLE 2 Bath Washing Trial number Additive Application Solventtemperature step PAB 2011-028 Delion F-6120(Tret 1.06% Water 125° C. NoN-103) PAB 2011-031 Griltex 2A 1.33% Water 160° C. No PAB 2011-032Griltex 2A 1.38% Water 160° C. No PAB 2011-044 Griltex D1523A GF 0.96%Ethanol/water 160° C. No 80:20 PAB 2011-048 Griltex D1523A GF 0.96%Ethanol/water 160° C. Yes 80:20 PAB 2011-057 Dehesive 971 3.83% Whitespirit D40 230° C. Yes PAB 2011-059 Vinnapas EP 441 2.55% Water 230° C.Yes PAB 2011-060 EP 441/WT 57 2.55% Water 230° C. Yes

Delion F-6120 (polyester wax from Takemoto), Griltex® 2A and Griltex®D1523A GF (copolyamides from EMS Chemie AG, business unit: Ems-Griltech,Switzerland), Dehesive® (silicone from Wacker-Chemie), Vinnapas® EP 441(vinyl copolymer from Wacker-Chemie) and Vinnapas® EP 441/WT 57(Si/vinyl copolymer blend from Wacker-Chemie) were used.

Determinations of the tear propagation force on the yarns thus obtainedwere carried out using the trouser test according to DIN EN ISO 13937-2.

The test conditions for the ribbon yarns were as follows: The samplelength is 150 mm, of which approximately 40 mm is separated using aneedle and the legs are fixed to the test device. The clamping length is50 mm, the drawing speed is 100 mm/min and the data logging takes placeover a 150 mm path.

The tear propagation path is divided into four equal sections from thefirst to the last recorded peak value. While the first section is notconsidered, all peak values of the remaining path are evaluated using aforce-drop detection of 15% from the peak value (Fmax peak).

The mean, standard deviation, and coefficient of variation weredetermined from 20 individual determinations (mean of Fmax peak (cN))per ribbon.

Table 3 shows the results, which are depicted again graphically in FIG.1.

TABLE 3 Trial PAB 2011-028 PAB 2011-032 PAB 2011-044 PAB 2011-048 PAB2011-057 PAB 2011-059 PAB 2011-060 Mean Mean Mean Mean Mean Mean MeanFmax Number Fmax Number Fmax Number Fmax Number Fmax Number Fmax NumberFmax Number peaks of peaks of peaks of peaks of peaks of peaks of peaksof [cN] peaks [cN] peaks [cN] peaks [cN] peaks [cN] peaks [cN] peaks[cN] peaks 0.35 328 9.94 19 6.15 29 7.88 28 0.48 341 23.80 18 2.54 380.38 327 6.41 25 6.16 42 4.83 38 0.24 382 8.66 31 4.73 18 0.38 329 6.0530 16.04 22 1.62 96 0.41 353 26.66 15 1.98 47 0.33 343 9.21 23 12.79 274.90 35 0.38 356 29.67 19 3.06 35 0.40 316 5.56 36 7.88 26 4.85 33 0.40355 14.32 11 6.23 14 0.43 329 3.42 49 10.08 25 2.33 83 0.31 383 8.04 291.60 84 0.36 351 6.76 24 10.15 27 6.37 50 0.60 372 3.47 57 2.29 71 0.33355 4.54 42 3.49 44 2.74 73 0.49 324 10.64 25 2.03 85 0.52 302 9.40 217.21 29 1.15 131 0.34 360 23.28 23 2.02 92 0.38 342 4.66 33 4.19 4112.18 31 0.34 370 28.90 19 1.21 165 0.28 355 12.54 14 10.41 24 13.86 160.68 280 6.20 43 1.16 138 0.27 339 2.42 73 4.91 29 3.06 58 0.44 358 6.6932 2.74 67 0.50 293 5.88 34 3.78 43 8.31 32 0.23 392 12.85 17 1.16 1490.32 335 10.82 20 3.16 51 4.09 43 0.59 301 17.97 16 2.66 58 0.28 3598.82 18 4.92 31 10.16 29 0.25 380 21.57 16 1.24 128 0.37 340 8.89 191.82 89 3.53 51 0.22 388 8.80 27 1.16 146 0.20 374 5.12 41 2.38 78 1.02159 0.30 366 8.17 35 1.09 149 0.22 364 6.41 28 11.77 23 3.76 39 0.19 39911.96 29 2.63 65 0.26 247 3.46 54 6.63 28 5.27 34 0.51 333 1.47 174 2.5462 0.30 357 7.24 24 8.43 27 2.78 46 0.26 386 5.18 37 2.77 51 n = 20 Mean0.34 334 6.88 31 7.12 37 5.23 55 0.38 359 13.92 34 2.34 83 s 0.08 2.693.81 3.59 0.14 8.84 1.28 v 24.20 39.15 53.48 68.50 35.32 63.53 54.61

The flexural strength of the fixed ribbon yarns was determined in thelaboratory based on ASTM D 4043. The test device is shown in FIG. 2.

The device parameters were as follows:

Sample size: 10 parallel fibersLength: 50 mm plus approximately 5 mm right and left for yarn fixing

Width: Approx. 10 mm

Support width: 25 mmL₀=10 mm (Distance of the pressure pad from the support height)Lmax=25 mm Travel and test pathV=500 mm/min Test speed

The results are summarized in Table 4.

TABLE 4 Flexural strength F max Trial number cN s v PAB 2011-028 177 0.317.04 PAB 2011-031 1.63 0.29 17.87 PAB 2011-032 1.58 0.16 10.16 PAB2011-044 4.28 0.81 18.91 PAB 2011-048 3.03 0.24 8.04 PAB 2011-057 2.730.49 17.8 PAB 2011-059 4.38 0.05 1.07 PAB 2011-060 3.39 0.18 5.23

To determine the temperature resistance and temperature behavior of theribbon yarns according to the invention, the basic yarn EN 140 HRT, dtex1880f280, and the ribbon yarn based thereon with the 1.8% copolyamide 2Aapplication were tested.

Tenacity and elongation at break were tested in a typical automobiletemperature range at −35° C., 23° C., 85° C., and 110° C. using a Zwickuniversal testing machine with a temperature chamber, based on ISO 2062(yarn) or DIN EN ISO 13934 (fabrics). In deviation from the ISOstandard, the clamping length of the test specimens was 250 mm insteadof 500 mm. In each case, the means from five determinations are shown.

TABLE 5 EN 140 HRT, dtex 1880f280, bobbin 47 - basic yarn EASF E- W BTTemp BF 11.3 N BT EAB mod. W BF W_BT N*mm/ ° C. N % cN/tex % cN/tex JJ/tex (tex*g/cm3) −35 180.5 0.8 96.0 16.6 665 3.602 0.019 17.0 23 153.01.3 81.4 20.2 449 4.043 0.022 19.0 85 129.4 1.9 68.8 19.8 312 3.3240.018 15.4 110 116.5 2.9 62.0 20.1 195 3.095 0.016 14.6

TABLE 6 Ribbon yarn with 1.8% Griltex 2A, bobbin 256 EASF E- W BT TempBF 11.3 N BT EAB mod. W BF W_BT N*mm/ ° C. N % cN/tex % cN/tex J J/tex(tex*g/cm3) −35 180.5 0.8 96.0 16.6 665 3.602 0.019 17.0 23 154.9 1.282.4 20.7 480 4.328 0.023 20.4 85 131.8 1.8 70.1 20.4 319 3.632 0.01916.9 110 118.6 2.7 63.1 20.8 199 3.319 0.018 15.6 BF = Breaking force,EASF = Elongation at specific force, BT = Breaking tenacity EAB =Elongation at break, W BF = Working capacity, W BT = specific workingcapacity

It can be gathered from Tables 5 and 6 that tenacity (see also FIG. 3),elastic modulus, and working capacity decrease with increasingtemperature and indeed to the same extent for the original yarn and forthe ribbon yarn according to the invention. This means that, despite allthe advantages—in particular in view of the weight savings when usingthe ribbon yarn—no disadvantages must be accepted when using thecopolyamide.

The elongation behavior increases somewhat with increasing temperature,but not significantly. In particular, the behavior at negativetemperatures is also still quite acceptable.

Subsequently, a woven fabric produced from ribbon yarn with a 1.8%copolyamide 2A application based on EN140HR, dtex 1880f280, with astructure of 4.4 fibers/cm in the plain weave conventional for airbags,was tested in the same way. The respective means from fourdeterminations are shown.

TABLE 7 Ribbon yarn with 1.8% Griltex 2A, bobbin 256 Temp Width Breakingforce Elongation at ° C. mm N break % −34.0 50 3841 20.0 22.8 50 320623.2 85.0 50 2718 23.4 110.0 50 2461 23.4

The fabric produced from the ribbon yarn according to the inventionbehaves according to the yarn: the strength decreases with increasingtemperature, and the elongation increases slightly.

1. A ribbon yarn comprising multifilament yarns based on polyamideand/or polyester, wherein not more than 5 filaments overlie one anotherwithin the ribbon yarn, wherein the ribbon yarn is fixed by theformation of a matrix comprising one or more fixing agents, wherein theone or more fixing agents are selected from a group consisting ofcopolyamides, copolyesters, silicones, and mixtures or blends thereof.2. The ribbon yarn according to claim 1, wherein not more than threefilaments overlie one another.
 3. An airbag fabric comprising the ribbonyarn according to claim
 1. 4. The airbag fabric according to claim 3,wherein the fabric is unsized, unwashed, and/or uncoated.
 5. A tirereinforcement comprising the ribbon yarn according to claim 1, whereinthe tire reinforcement optionally comprises at least one adhesionpromoter.
 6. A textile, wherein the textile comprises the ribbon yarnaccording to claim
 1. 7. The ribbon yarn according to claim 1, whereinthe matrix consists of the one or more fixing agents.
 8. The ribbon yarnaccording to claim 1, wherein the individual filaments forming themultifilament yarn are aligned parallel and are side-by-side.
 9. Theribbon yarn according to claim 1, wherein the ribbon yarn is suitablefor use in an airbag.